The climate is changing: the Arctic Dipole emerges
The dramatic loss of Arctic sea ice in recent years has created a fundamental new change in the atmospheric circulation in the Northern Hemisphere that has sped up sea ice loss and is affecting fall and winter weather across most of the Northern Hemisphere, according to several recent studies. Arctic sea ice loss peaks in September and October, exposing a large area of open water that heats the air above it. This extra heat has helped drive September - November air temperatures in the Arctic to 1°C (1.8°F) or more above average over about half of the depth of the lower atmosphere (Figure 1). This deep layer of warm air has grown less dense and expanded, pushing the top of the troposphere (the lower atmosphere) higher. The result has been a decrease in the pressure gradient (the difference in pressure) between the North Pole and mid-latitudes. With not as much difference in pressure to try and equalize, the jet stream has slowed down in the Arctic, creating a major change in the atmospheric circulation for the Northern Hemisphere.
Figure 1. Cross section of Arctic temperature anomaly from 1000 mb (the surface) to 300 mb (roughly, the height of the top of the lower atmosphere or troposphere). Cross section is taken along the Date Line (180°W), from 60°N latitude (left side) to the North Pole (right side), for September - November for the 12-year period 1998 - 2009. Three year averages were done to reduce the amount of year-to-year noise associated with natural variation. Other cross sections along different lines of longitude show similar results, though typically with more warming aloft and less warming at the surface. Image credit: NOAA/ESRL.
A new atmospheric pattern emerges: the Arctic Dipole
In a 2008 article titled, Recent radical shifts of atmospheric circulations and rapid changes in Arctic climate system Zhang et al. show that the extreme loss of Arctic sea ice since 2001 has been accompanied by a radical shift of the Arctic atmospheric circulation patterns, into a new mode they call the Arctic Rapid change Pattern. The new atmospheric circulation pattern has also been recognized by other researchers, who refer to it as the Arctic Dipole (Richter-Menge et al., 2009). The old atmospheric patterns that controlled Arctic weather--the North Atlantic Oscillation (NAO) and Arctic Oscillation (AO), which featured air flow that tended to circle the pole, now alternate with the new Arctic Dipole pattern. The Arctic Dipole pattern features anomalous high pressure on the North American side of the Arctic, and low pressure on the Eurasian side. This results in winds blowing more from south to north, increasing transport of heat into the central Arctic Ocean. The Arctic Dipole pattern occurred in all summer months of 2007 and helped support the record 2007 summer reduction in sea ice extent (Overland et al., 2008). Overland et al., 2010 also found that the Arctic Dipole pattern tended to create an increase in easterly winds in the lower half of the atmosphere of 40% in fall, between 2002 - 2008. Fall 2008 through spring 2009 featured the old AO pattern. The new Arctic Dipole pattern re-appeared in June - July 2009, but the old AO pattern dominated in August - September, resulting in greater sea ice extent than in 2007 and 2008. The Arctic Dipole pattern was active again in October, inactive in November, and reasserted itself this December. As a result, Arctic sea ice reached a new record minimum for a 10-day period in early November, increased above record lows during late November and early December, and appears poised again to reach a new record minimum later this December (Figure 2).
Figure 2. Sea ice extent in the Arctic for this year (blue line) compared to the record low year of 2007 (green line) and 1979 - 2000 average (gray line). One could make the ice loss looks less significant by using the full satellite data record from 1979 - 2008 for the average. Image credit: National Snow and Ice Data Center.
Arctic Dipole blamed for colder winters in East Asia
It turns out that the new Arctic circulation patterns help to intensify the Siberian High, a large semi-permanent region of surface high pressure prevalent in winter over Siberia. According to Honda et al. (2009), this results in increased flow of cold air out of the Arctic in early winter over eastern Russia, Japan, Korea, and eastern China, causing colder temperatures. By late winter, the pattern shifts, resulting in colder than average temperatures from East Asia to Europe.
Arctic Dipole blamed for drier winters in Northern Europe
Francis et al. (2009) found that during 1979 - 2006, years that had unusually low summertime Arctic sea had a 10 - 20% reduction in the temperature difference between the Equator and North Pole. This resulted in a weaker jet stream with slower winds that lasted a full six months, through fall and winter. The weaker jet caused a weaker Aleutian Low and Icelandic Low during the winter, resulting in a more negative North Atlantic Oscillation--a pattern that usually brings reduced winter precipitation over Alaska and Northern Europe and increased precipitation over Southern Europe. A more negative NAO also tends to bring cold winters to eastern North America and Europe. Though it was not mentioned in the article, reduced Arctic sea ice may also cause dry early winter conditions in the U.S. and the Caribbean (Figure 3). The authors noted that strong La Niña or El Niño events can have a much larger influence on the wintertime atmospheric circulation, which will overshadow the changes due to Arctic sea ice loss.
Figure 3. Difference in early winter precipitation (November - January) between five years that had low Arctic sea ice (2005, 2006, 2007, 2008, and 2009), and five years that had unusually high Arctic sea ice extent (1981, 1984, 1986, 1989, 1993). Note that low sea ice may be responsible for dry conditions in early winter for the Caribbean and most of the U.S.
Commentary
Arctic sea ice loss appears to have created a new atmospheric circulation pattern that brings more warm air in the Arctic, creating a positive feedback loop that causes even more sea ice loss. This feedback loop increases the likelihood that an ice-free Arctic in the summer will indeed come by 2030, as many Arctic experts are predicting. It's worth noting that such an atmospheric circulation shift was not predicted by the climate models. Indeed, the loss of Arctic sea ice over the past three years exceeds what any of our models were predicting (Figure 4). While we can rightly criticize these models for their inaccuracy, we should realize that they are just as capable of making errors not in our favor as they are of making errors in our favor.
Figure 4. Arctic sea ice extent from observations (thick orange line) and 13 model forecasts used to formulate the 2007 IPCC report (light lines). The thick black line is the multi-model ensemble mean, with the standard deviation plotted as a dashed black line. Image has been updated to include the observed 2008 and 2009 measurements. None of the models predicted the record 2007 sea ice loss. Image credit: Arctic sea ice decline: Faster than forecast by Stroeve et al., 2007.
References
Francis, J.A., W. Chan, D.J. Leathers, J.R. Miller, and D.E. Veron, 2009, "Winter Northern Hemisphere weather patterns remember summer Arctic sea-ice extent", Geophysical Research Letters, 36, L07503, doi:10.1029/2009GL037274.
Honda, M., J. Inoue, and S. Yamane, 2009. Influence of low Arctic sea - ice minima on anomalously cold Eurasian winters, Geophys. Res. Lett., 36, L08707, doi:10.1029/2008GL037079.
Overland, J. E., M. Wang, and S. Salo, 2008: The recent Arctic warm period, Tellus, 60A, 589.597.
Overland, J. E., and M. Wang, 2010: Large-scale atmospheric circulation changes associated with the recent loss of Arctic sea ice. Tellus, 62A, 1–9.
Richter-Menge, J., and J.E. Overland, Eds., 2009: Arctic Report Card 2009, http://www.arctic.noaa.gov/reportcard.
Simmonds, I., and K. Keay (2009), Extraordinary September Arctic sea ice reductions and their relationships with storm behavior over 1979.2008, Geophys. Res. Lett., 36, L19715, doi:10.1029/2009GL039810.
Wu, B., J. Wang, and J. E. Walsh, 2006: Dipole anomaly in the winter Arctic atmosphere and its association with sea ice motion. J. Climate, 19, 210-225.
Zhang, X., A. Sorteberg, J. Zhang, R. Gerdes, and J. C. Comiso (2008), Recent radical shifts of atmospheric circulations and rapid changes in Arctic climate system, Geophys. Res. Lett., 35, L22701, doi:10.1029/2008GL035607.
Jeff Masters
Reader Comments
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Includes step by step instructions.
Fables of the Reconstruction
(Or, How to Make Your Own Hockey Stick)
if you were to take the situation into your own hands with an RO system, it wouldn't really matter what actions, if any, the municipal water supply company takes.
North Atlantic Gyre
North Pacific Gyre
South Pacific Gyre
Indian Ocean Gyre
Our current set of physics concerning a hurricane's central pressure is completely dependent on latent heat from condensation.
This paper is throwing that out and proposing that the physics is really about how much less volume a liquid water molecule consumes than a gaseous water vapor molecule (which is a lot less).
For example, if you put a half-empty bottle of flat soda in a fridge, the bottle will contract from being both being chilled and the water vapor in the bottle condensating. your bottle literally takes up just a little less space that it did when you put it in the fridge. So your fridge must have taken in just a little outside air to compensate (unless it is capable of maintaining a vacuum!).
That same phenomenon, without as much chilling, just the condensation, really is what this paper is about. That same contraction in the amount of space your soda bottle consumes, but miles across and far more efficient than that, and with a constant supply of water vapor, would produce an attempted vacuum in the atmosphere. An area of deepening low pressure. That is the gist of it...overly simplified.
;-)
oh, wait...my bad...i'm supposedly incapable of understanding complex, technical things...hehehe
Oversimplified for whom, Science Guy? RTVF majors who stumbled into the WU blog and should be reading HiLights (is that still published? I should get a subscription if it is.)
Thank you for that! It will be really interesting to follow this...hope it won't be screwed up like ... never mind... (note to blog: somebody please keep back-up copies of the original data).
Pearland: You be bad. Very funny, tho! Dr. Jeff did apologize for his wording...I think in response to NRAamy, HA! Even he be scared of HER wrath, hehe.
Can anyone help me with 2 questions?
1. The hole in the ozone layer seems to be shrinking (yea). Will the increased ozone, increase temperature and if so, how much?
2. If the high pressure over the arctic slows the polar jet and decreases exchange with the tropics, why doesn't that help to cool the arctic back down? Is there a possible reverse of the diplole set up? Will these shifts lead to a slowing of the Gulfstream that would also help cool the arctic back to "normal"?
Koalas, penguins at risk of extinction: study
by Marlowe Hood Marlowe Hood Mon Dec 14, 6:27 am ET
Link
COPENHAGEN (AFP) – Climate change threatens the survival of dozens of animal species from the emperor penguin to Australian koalas, according to a report released Monday at the UN climate summit.
Rising sea levels, ocean acidification and shrinking polar ice are taking a heavy toll on species already struggling to cope with pollution and shrinking habitats, said the study from the International Union for the Conservation of Nature (IUCN), an intergovernmental group.
"Humans are not the only ones whose fate is at stake here in Copenhagen -- some of our favourite species are also taking the fall for our CO2 emissions," said Wendy Foden, an IUCN researcher and co-author of the study.
The report details how climate change undermines the viability of 10 species, including the leatherback turtle, the beluga whale, clownfish, the emperor penguin and salmon.
Australia?s iconic bear-like koala faces malnutrition and ultimate starvation as the nutritional quality of eucalyptus leaves declines as CO2 levels increase, the report added.
Polar species are especially hard hit.
The ringed seal is being forced further north as sea ice it relies on for rearing its vulnerable pups retreats every decade.
The emperor penguin, remarkably adapted to thrive in harsh Antarctic conditions, faces similar problems. Reduced ice cover makes it harder to mate and raise chicks, and has caused a sharp decline in the availability of krill, a major food source.
As once-frozen tundra gives way to forest, the common red fox has moved northward, where it hunts and competes with its far rarer arctic cousin.
The beluga whale is doubly threatened by global warming: loss of sea ice makes it tough to find prey, and the rush to open new maritime routes is likely to result in deadly ship strikes, as happens elsewhere.
"For a large portion of biodiversity, climate change is an additional and major threat," said Jean-Christophe Vie, deputy head of the IUCN?s Species Programme.
In tropical regions, more than 160 species of staghorn corals -- and the tens of millions of people that depend on healthy coral reefs for their livelihood -- are dying off due to ocean acidification, a direct result of warming seas.
For clownfish, brought to the screen by Hollywood in the animated blockbuster "Finding Nemo", the changing ecosystem impairs sense of smell, which they use to find the sea anemones they rely on for protection.
Salmon stocks are dropping off not just from overfishing but because lower oxygen levels resulting from increased water temperatures boost susceptibility to disease and disrupt breeding.
The United Nations climate talks are tasked with forging a durable solution to global warming and helping poor countries cope with its consequences. They are set to end with a summit on Friday with around 120 leaders attending.
My yard is as wet as it has ever been. Freakin mudhole from all the rain lately. Please God! No more (for a few weeks anyway).
National Situation Update: Monday, December 14, 2009
Homeland Security Threat Level: YELLOW (ELEVATED).
Significant National Weather
West
Some light snow showers may continue through this afternoon over the central and northern Rockies and the northern Wasatch with snow accumulations of a few inches are possible. Rain and mountain snow will become heavier throughout the day and will continue through Tuesday morning. After a brief break Tuesday morning another round of rain and snow will move in Tuesday afternoon and evening.
Rainfall amounts of one to three inches are possible in the lower elevations with four to five inches possible in the foothills of the Cascades. Snowfall of one to two feet is possible in the Cascades with up to a foot of snow possible in the interior mountains. The valleys east of the Cascades could see snow accumulation of up to four inches. Southern California and the Southwest will remain dry today and Tuesday.
Northeast
The region should remain dry today with a few sprinkles possible tonight in the central and southern parts. Light snow or flurries are possible by Tuesday morning.
South
Rain will continue today from eastern Texas through the Florida Panhandle and by tonight the rain will move northeast into central Mississippi, central and northern Alabama and central and northern Georgia. Tonight through Tuesday the rain will continue to expand into the Carolinas, while remaining in eastern Texas to northern Georgia. One to three inches of rain is expected throughout the area with four to five inches of rain possible in localized areas across eastern Louisiana, southern Mississippi, and southern Alabama.
Midwest
Light to moderate snow is expected through tonight across the upper Midwest and northern Great Lakes. Snow accumulation of two to six inches is possible with the heaviest snow forecast close to Lake Superior in northern Michigan. Heavy snow squalls are likely on Tuesday around the Great Lakes, to the east and southeast of the lake shore. (NOAA’s National Weather Service, Various Media Sources)
Disaster Declaration Activity
The Governor of Kansas has requested a Major Disaster Declaration as a result of a severe winter storm that occurred November 14-16, 2009. The Governor is specifically requesting Public Assistance for three counties and Hazard Mitigation statewide. (FEMA HQ)
Last Modified: Monday, 14-Dec-2009 07:31:36 EST
as for question 2, that is a very interesting logical deduction. it actually would not surprise me to find a negative feedback setup like that that would tend to moderate temperatures over the long term. but, i don't have a whole lot of information WRT that phenomenon. sorry! :)
Sux, if accurate. Outside of why the climate change or that it is changing beyond what would be going on without us present, have you read my blog post?
Of course, I don't want to see any species go extinct and am all for mitigation attempts, things do sometimes fail to adapt to natural changes...
That would be nice. I know the deep south could use a break but, the tropics could use a drink.
Are those predictions or measurements?
Increased CO2 should not change the nutritional value of leaves, in and of itself. It should make it easier for the tree to grow food for the Koala.
Leatherbacks suffer from lack of nesting habitat and light pollution but overfishing has caused a bloom of jellyfish (their major food source).
What part of the ecosystem change blocks a clown fish's sense of smell? Is that change preventable?
As for acidification and ocean 02 levels... yeah, that just sucks, but I have not seen good, distributed spatial monitoring of it yet.
On your personal blog, the circa 1920, H.G. Wells comments? Yes, and it was good, but you know silly RTVF me was mostly checking out related video clips...will re-read, seriously.
Hydrus, thanks, from your post out to the Universe, re saving critters...if not, we're bound to be part of that extinct 99 percent soon!
Things are Badly amiss.
One cant "quantify" everything 100%.
But the data as whole is not the tell all,..just ask folks over 80,famers,and global residents.
And by the time comes that the world en masse realizes the dilemma we ALL face.
We will come down to a lil ol saying..
Well,we were told,..and like Apollo 13 when the Electrical Systems officer said,"we dont have to conserve power,..we have to turn everything OFF".
Only then did the minds of the magt team come to realize,..Jezus Gov. Crist!'
We do!!!
Look at the whole data..if one cant see that somethings terribly amiss,then one isnt really looking...there only hoping their view is still,a reality.
..or Fools Gold you could say.
As for Florida rain, the Peninsula is wet mostly near Tampa and the Panhandle is soaked but the armpit is dry based on USGS stream level. I'm not SURE why that is.
Did Jacksonville issue a "Front Stops Here." statement?
Snowfall Warning : Greater Victoria Issued at 4:40 AM PST Monday 14 December 2009
Major winter storm with heavy snow expected for the south coast beginning late in the day with 10 to 20 cm snowfall accumulation by Tuesday. This is a warning that significant snowfall is expected or occurring in these regions. Monitor weather conditions..Listen for updated statements.
A strong Arctic ridge of high pressure over the British Columbia interior will continue to bring cold dry Arctic air across the north and central coast regions. Strong outflow winds through the inlets and valleys will combine with cold temperatures to give wind chill values of minus 20 or below to the north and central coasts today through Tuesday. Meanwhile, a moist frontal system arriving from the pacific will clash the Arctic air over the south coast beginning late today. Snow at times heavy will begin late this afternoon over Vancouver Island and early this evening for the mainland. Total snowfall amounts of 10 to 20 centimetres are expected before the snow changes to rain on Tuesday. Freezing rain will occur during the transition to rain particularly over the Lower Fraser Valley on Tuesday and freezing rain warnings will likely be issued later today. Strong easterly winds 50 to 70 km/h will also develop this evening over West Vancouver Island ahead of the frontal system and ease overnight.
Good questions, all! Obviously, we need to see full report...and that means I will need to bug all of you (yet again) to "dumb it down" for me, LOL (I can HEAR you groaning, Aggies!)
I posted an article last week about CO2 interfering with fishees' sense of smell to sense predators; it hasn't happened yet...was performed in a lab, with double "normal" amounts of CO2. I just try to read the best (semi-?) objective articles for the "masses" I can find...and throw them out there hoping you all might be interested and be able to shed light, etc. I'm a pretty good "googler"; crappy in Science except for my one A in Environment/Ecology 101 a zillion years ago...back then it was under the "Ag Sciences" at U.MD. I don't even think it was called Ecology back in the Dinosaur era :)
Patrap, you ever visit a childhood home after not laying eyes on it for a couple of decades? I did once. And the place was easily twice as large in mind's eye than in real life. I have seen this or heard about this same type of event from at least 2 other people.
Perception of details over a long period of time gets skewed.
This is not even including the natural cycles of climate that span 30 and 60 years, which, in the presence of a perfect memory of scale, would still give the impression of change over time. This means nothing at all with respect to attributing changes to tailpipes.
"Look at the whole data..if one cant see that somethings terribly amiss,then one isnt really looking...there only hoping their view is still,a reality.
..or Fools Gold you could say."
The one-sided, full-of-certainty statements, like you present here, are exactly what makes me want to look at "the whole data". Something does appear to be terribly amiss...
CRU Takes Down Briffa Tree Ring Data and More
p & a..Im speaking to atmo,not you aggie friend..as per a phone conversation we had months ago.
Your way off the mark as to what Im relaying.
And please dont speak for me,nor put words in my post.
Thats inane and childish
Thanks always, Pearland!
Patrap, something to help get you through the rainy days! Merry early Christmas:
(DC-based) Marines Return Home (w/video)
If it is our destiny, then it shall be done. We dissapear like star dust! like we were never here
Still means nothing outside of it appears to have changed to you...
I don't think you know me as well as you think you do for this affront, accusatory 'tude.
I have testified for both scenarios, and others, without the quotes, as an expert witness.
The results I give either side are simply a scientific analysis. I refuse to have any bias towards anyone, period. I have even gone so far as to essentially refuse a couple of cases by letting the lawyers know that my analysis would hurt their cases, not help. I would rather turn down money in my pocket than give a biased analysis. I have never had a lawyer ask me to change anything, either, as they know better.
My analysis, in any case, is based entirely on observational data, where available. And where there are few, if any, very nearby observations, some modeling verified against all existing, official observations.
ironically, it sounded like you were accusing him of biasing data to fit his perception or mode of income. i didn't want to misunderstand your post...simple as that.
http://www.nasa.gov/mission_pages/hurricanes/archives/2009/2008_video.html
Atmo and I are mutual friends..so I'd use a "real"question,instead of innuendo.
Its less confusing.
Im a big boy,been slapped nuff round these parts for quite a spell.One more only steels the Jarheads resolve,..LOL
Sorry you mistook the thread
No Harm,no foul.
I do like the poetry of your words, Rita; I'm also enamored of the concept of "free will" -- that we do have a hand in what has been so graciously provided for us, and can choose to go down one road or the other!
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